Semi-automatic firearm



FIG. 1 is a left elevation view of a semi-automatic firearm, showing my new design;

FIG. 2 is a right elevation view thereof;

FIG. 3 is a back elevation view thereof;

FIG. 4 is a plan view thereof;

FIG. 5 is a bottom view thereof; and,

FIG. 6 is a front elevation view thereof. 

I claim, the ornamental design for semi-automatic firearm, as shown and described. 